Tibial and Fibular Shafts

hapter 6 included proximal tibial fractures. Chapter 8 will review distal fractures about the ankle. This chapter will focus on the shaft of the tibia and fibula with respect to fracture management and leg length discrepancy.

Trauma

Fractures of the tibial and fibular shafts are among the most common long bone fractures in adults (average age 37), teenage males (15% of all fractures), and comprise 4% to 5% of all childhood fractures. Fibular fractures are usually associated with tibial fractures (see Fig. 7-1). Therefore, the focus will be on tibial injuries. The distal two thirds of the tibia is most often involved. Also, the lower leg is the most common site of combined osseous and soft tissue injury. The relatively exposed subcutaneous location of the tibia makes it vulnerable to direct high-velocity injury such as motor vehicle accidents or gunshot wounds. Direct trauma usually results in transverse, segmental, or comminuted fracture of the tibia with associated fibular fractures. Indirect trauma generally results in oblique or spiral fractures (see Fig. 7-2). Overuse injuries may also result in stress fractures of the tibia and fibula. Fractures should be described by precise anatomic location, pattern of the fracture line, position of the fragments, degree of comminution, and whether they are open or closed.

Classification

Treatment of tibial shaft fractures includes closed and open approaches. Treatment choice is based on the type of fracture, whether open or closed, patient status, and surgical preference. There are multiple classification systems designed to assist with treatment and prognosis. Gustilo and Anderson’s classification is specifically designed for open wounds, a common feature of tibial shaft fractures.

Orthopaedic Trauma Association classification

Type A: Simple fractures

A1—spiral fractures (Fig. 7-2)

A2—oblique fractures

A3—transverse fractures (see Fig. 7-3)

Type B: Wedge fractures (see Fig. 7-4)

B1—spiral wedge fractures

B2—intact bending wedge fractures

B3—comminuted wedge fractures

Type C: Complex fractures (see Fig. 7-5)

C1—spiral complex fractures

C2—segmental complex fractures

Gustilo and Anderson classification

Type I: Wound clean and <1 cm

Type II: Wound larger than 1 cm without extensive soft tissue damage

Type IIIA: Extensive soft tissue wound (≥10 cm), periosteum intact

Type IIIB: Periosteal stripping requiring flap coverage

Type IIIC: Above plus vascular injury requiring vessel repair (see Fig. 7-6)

Fig. 7-1 A: Isolated fibular fracture (arrow) due to a direct blow. Cast immobilization. Anteroposterior (AP) (B) and lateral (C) radiographs at 6 weeks demonstrate organizing callus formation.

Fig. 7-2 Minimally displaced spiral fracture of the distal tibia due to a twisting injury in soccer. Anteroposterior (AP) (A) and lateral (B) radiographs demonstrate the tibial fracture (arrow) with no associated fibular fracture.

Fig. 7-3 Anteroposterior (AP) (A) and lateral (B) radiographs of minimally displaced transverse fractures of the mid tibia and fibula with cast immobilization.

Fig. 7-4 Anteroposterior (AP) radiograph demonstrating a wedge (butterfly fragment) fracture (arrow) of the proximal tibia with adjacent comminuted fibular fracture.

Imaging Techniques

Imaging of tibial and fibular shaft injuries can be accomplished with anteroposterior (AP) and lateral radiographs for complete fractures (Figs. 7-1 to 7-5). Knee and ankle should be included. Subtle stress injuries or undisplaced fractures may be more easily assessed with magnetic resonance imaging (MRI). Radionuclide scans can also be useful for detection of subtle fractures. However, magnetic resonance (MR) features are typically more specific. Angiography may be required in patients with advanced soft tissue injury who may require vascular repair (Gustilo and Anderson IIIC) (Fig. 7-6).

Treatment Options

Goals for management of tibial fractures include maintaining length, restoring normal weight-bearing alignment, and preservation of soft tissues. Alignment and rotation should be corrected to near anatomic position. The ankle and knee joints must be parallel. There should be no >5 degrees of varus or valgus angulation, 10 degrees of anterior or posterior angulation, 10 degrees of rotation, and 1 cm or less of leg length discrepancy (see Fig. 7-7). In children younger than 8 years, apposition is less critical. In older children, at least 50% apposition should be achieved (see Fig. 7-8). Treatment options include closed reduction with cast or brace immobilization, external fixation, intramedullary nailing, and open reduction with plate and screw fixation.

Closed Reduction with Cast or Brace Immobilization

Initially, all tibial fractures should be treated with a long posterior splint with the knee in flexion and the ankle in neutral position. Compartment syndrome is a concern and should be monitored. Stable undisplaced fractures can be treated with cast immobilization in 3 to 5 days after initial swelling has decreased (Fig. 7-8). There are several cast approaches including long leg casts with slight knee flexion and patellar-tendon bearing (PTB) casts (see Fig. 7-9). In either situation, early weight bearing is important. In adolescents long leg cast immobilization for 6 weeks is followed by progressive weight bearing in a PTB cast for an additional 4 to 6 weeks. A brace can also be used after several weeks of cast immobilization to increase joint motion and facilitate weight bearing. Serial radiographs are important to assure fracture stability. Callus begins to form at approximately 6 to 8 weeks following the injury.

Fig. 7-5 Complex open fracture. Antero-posterior (AP) (A) and lateral (B) radiographs of a complex open fracture with displaced comminuted fractures of the tibia and a comminuted segmental fibular fracture.

Fig. 7-6 Gustilo and Anderson type IIIC injury. Anteroposterior (AP) angiographic views of the knee (A) and leg (B) demonstrating a complex open fracture with occlusion of all but the posterior tibial artery below the trifurcation.

Fig. 7-7 Anteroposterior (AP) radiograph following closed reduction of comminuted mid tibial and fibular fractures. There is 17 degrees of medial angulation at the tibial fracture site and the ankle is not parallel to the knee.

External Fixation

External fixation approaches are commonly used with tibial shaft fractures due to the relatively high frequency of open fractures with varying degrees of soft tissue injury. Fixation is easily applied and allows adjustability of fragments and access to soft tissue wounds (see Fig. 7-10). Pin or wire placement is accomplished to avoid critical anatomic structures such as neurovascular areas (see Fig. 7-11).

Indications for external fixation

Open fractures with soft tissue injuries (see Fig. 7-12)

Management of fractures with bone loss

Closed severely unstable fractures

Closed fractures in patients with:

Burns

Head injuries

Neurosensory deficits

Compartment syndromes

Bone lengthening procedures

Treatment of the following:

Nonunion

Infected nonunion

Malunion

External fixation (see Chapter 2) is accomplished using unilateral, ring, or hybrid fixation devices. There are advantages and disadvantages to external fixation techniques.

Advantages

Stabilization away from fracture site

Wound access

Wide variety of fixation options

Adjustable during treatment

Minimal interference with adjacent joints

Mobilization of patients with weight bearing

Disadvantages

Soft tissue injury and contractures

Pin tract infection

Loss of reduction

External fixation can be converted to intramedullary nail fixation (see Fig. 7-13) or uncommonly internal fixation with plate and screw fixation.

Intramedullary Nail Fixation

Intramedullary nails (see Fig. 7-14) are commonly used in adult tibial fractures with exception of proximal third fractures where results are less than optimal. Intramedullary nails may be placed with or without reaming using open or closed techniques. In children, this technique has not been used extensively due to the potential of proximal physeal injury and growth disturbance. Flexible intramedullary nails can be used in certain situations. Intramedullary techniques are most optimal with closed fractures. The risk of infection is increased with open fractures, especially Gustilo and Anderson type II or III injuries. However, excluding type IIIB and IIIC injuries, the success of intramedullary nail fixation of both closed and open fractures is high. In closed fractures reaming is preferred with healing at 4 months compared to longer healing times for unreamed nail fixation (6.5 months) (see Fig. 7-15).